Effect of neurotoxic pesticides on the feeding rate of marine mussels (Mytilus edulis)

The effects of selected neurotoxic pesticides on the feeding rate of marine mussels (Mytilus edulis) were determined. Two organochlorine pesticides, lindane and endrin, two acetylcholinesterase-inhibiting compounds, dichlorvos and carbaryl and two pyrethroids, flucythrinate and permethrin, were studied. No evidence was found for any specific neurotoxic effect of the organochlorines and pyrethroids on feeding efficiency. In contrast, dichlorvos and carbaryl inhibited the enzyme acetylcholinesterase in mussel gills and were more toxic to feeding efficiency than could be explained by a narcotic mechanism of toxicity alone. Dichlorvos also caused clear behavioural changes in the mussels. The significance of these observations for the application of mussels to impact assessment in the marine environment is discussed.